Do a runner
Definition 1 of 1
Pro Tip 1/3Slang Expression
Used in casual, informal situations. Not suitable for formal writing or speeches. 
At parties, someone might joke about doing a runner to avoid cleaning up.
Pro Tip 2/3Negative Connotation
Implies dishonesty or irresponsible behavior. Used when someone avoids responsibility. 
He was supposed to help with the project, but he did a runner.
Pro Tip 3/3UK Specific
Commonly used in the UK, might not be understood or used in other English-speaking countries. 
In the US, people were confused when I said he did a runner from the bar.